Mechanism for synchronizing clocks



BEST AVNLABLE COP? March 2 1926.

T. s. cAsNER .MBCHANISM FOR smoaaomzme CLOCKS 5 Sheets-Sheet ori m 'Fi1'ed March 24. 1921 17 SEGO/YO/l/PY CLOCKS attorney 1 BEST NJAELABLE COP ,MarcH 2 1926. 1 1,575,096

T. s. CASNER MECHANISM FOR syuczmomzme CLOCKS Original Filed March 24, 1921 5 Sheets-Sheet gpwmm y a 3 1 may, 5 j

BEST AVAA LABLE COPE Maire 2 1926. 1,575,096

T. S. CASNER MECHANISM FOR SYNCHRONIZING CLOCKS original Filed March 24, 1921 5 Sheets-Sh'et 5 S nuuntoz imfn sks' I I 1 itozkuis,

0. BEST AVNLABLE 00.

March 2 1926. 1,575,096

MECHANISM FOR SYNCHRONIZING CLOCKS I ri fi Filed March '24, 1921 5 Sheet s Sheet .4

' anvqmtoz Pl nner i 26.

UNITED *sragrss PATENT OFFICE THADDEUS STEPEENS CA SNEB, F PLAINFIELD, NEW JERSEY, ASSIGNOB, BY MESNE ASSIGNMENT a. conrona'rrdn or nnnawann IECHAN 'IBK Z FOB SYNCHRONIZING CLOCKS.

The present invention relates to mechal0 ni'siii for synchronizing clocks and particularly. to electro-magnetic mechanlsm by means of which a clock may be periodically corrected by electrical impulses transmitted through space. These'impulses are known ertzian waves orvibrations and may "be transmitted from the sending station for long distances at such a high'ratc of speed =,that,tlie lapse oftime between the instant of sending from the transmitting station, 0 and the instant of receiving at the receiving station, is negligible. Realizing .the advan-- tages of utilizing the Hertzian waves in transmitting a'daily time signal throughout the United States with the end in view of 25 synchronizing the reference time .pieces of the country, the United States Government now sends out daily at 12 oclock noon and 10 o'clock at ni ht a series of signals by wireless telegrap h from a station adjacent the clock which is used as a standard time ,piece for all other time pieces of the country. It has been found necessary to send out, instead'of a single signal upon the instant of 12.0clock, a series of warning sig- 3 'nals whichterminates in the final signal which indicates either noon or oclock at night, as the case may be. For instance, it is now the practice of the Government to be gin sending such signals five minutes before 40 12 oclock, such signals being sent daily in accordance with a definite prearranged code by means of which the operators at the receiving stations are apprised of the fact that the time signal is about to begiven in order that they may be fully prepared to receive it. In accordance a'vith the present code the first noon signal occurs at five minutes before '12 oclock and signals are given r atone second intervals until the final signal,

no. 455,262. Renewed February 5, 1925.

which is sent forth exactly at 12 oclock lhe series of signals is broken, however, by intervals of silence so that the receivers may S, TO'BADIO ELECTRIC CLOCK CORPORATION, OF YORK, Y.,.-

note the passing of the minutes and so they may also clearly distinguish the signalgiven at 12 oclock from all other signals. For this purpose the, 29th second signal of each minute series is omitted and also the last five second-signals of each minute series are omitted for the first four minutes, but in the last minute series the 10 second-signals immediately preceding the final noon signal are omitted to further distinguish this particular'signal from all others.

It has heretofore been the practice of operators of wireless re eiving stations through the country to liste to the series of signals and to operate a stop watch upon the final signal, with which watch the other-clocks may be manually synchronized. This involves not only the necessity of having anexpcrt wireless operator wherever accuracy of clocks is desired, but is hardly an accurate method inasmuch as the operator may not, start his stop watch upon the exact instantof hearing the signal, and also the stop watch itself may be inaccurate and the clocks which are to be corrected from the stop watch may not be accurately synchronized therewith by the person performing this function. \Vhere electric clock systems are utilized, involving as they do a master clock and a large number of secondary clocks all svchronized with the master clock, it is desirable that the system be corrected daily,

that. is, that the master clock be corrected daily in order that'the entire clock system may give accurate time indications By such daily corrections the installation of a cumbersome and expensive master clock of great accuracy may be avoided but such daily corrections by wireless have heretofore necessitated the pressure of an experienced wireless expert, which involvesa considerable expense where such expert is not also needed for other purposes.

The present invention' provides means whereby a clock may be automatically corrected by the noon or night wireless sig- 16 It has heretofore been clocks may be synchronized through space PIP-ET AVAILABLE COPY nalsof the Government, thereby enabling a. clock of average cost and accuracy, wh ch would ordinari each day,-

've i ractically accurate time 8 indications an wi out the necessity of'hav- .ing' a' wireless operator present. Tins electro-mechanical synchron zin mechanism may be installed in .all buil ings, such as office buildings, hotels, public buildings and z in private homes without great xpense, in-

' volving the installation of only a standard wireless receiving set of any well known kind, the installation of a transmitting set being ofcourse unnecessary.

byniea'ns'of electrical impulses .but such h mechanisms have not been capable of accomplishing the objects of the present invention, the problem of selecting the correctsignal 0ft 6 series of"signa1 s and automatically correcting a clock being vastly different ,from the roblems solved by the prior inventors w ose apparatus Wlll either funcgi tion upon receiving a'smgle signal, whether jthis signal is the proper one or not; or will function only when'the signals are sent by a special transmitting apparhtus. The prohlem of providinga mechanism for automatiq-cally setting a clock by one of a series of similar signals, such as now sent out daily by the Government,"'has heretofore remained unsolved;

- In the following description and in the 5 accompanying drawings I discloseone em- "bodiment." of myinvention by way of example. It will be obvious that the device maybe altered to suit different conditions and to become operative on receipt of different codes of signals and may he modified in various other ways within the scope of the invention, which is' of broad character. In the drawings: Figure-1. is awiw from the front of a .f master clock having the correctin device incorporated therewith, the casing, dial, and hands having been omitted;

F igure 2 is a side view of the same; .Figure 3 is a section on the line 3-3 of Figure 2, part of the clock mechanism havin been broken away;

ignre 4 is a rear elevation, part being broken away;

Figure 3 is a section on the line-55 of Figure 1; v

Figure 6 is a sectional view through the aligned drive shaft and second hand shaft of the clock;

Figure 7 is a front elevation of a portion of the mechanism illustrated in Figure 1, certain of the moving parts being shown in different positions;

Figure '8 is a section on the line 8-8 of F igure 7; igure 9 is a section on the line 9-9 of y vary a few seconds in time move is arm in a different position;

on the line 11--11 suggested that Figure 1 but showing a portion of a'movable arm which is not present in that section Fi ure 10 is a. similar view showing'the Figurell is a section ofFigurel; p Figure 12 is a side viewof a switch controlling the secondary clock circuits, showin in section the switch operating cam;

igure -13 isan elevationof the same;

Figure 14 is a schematic view of the electro-mechanical'clock correcting mechanism;

Figure 15 is a view of a portion M this mechanism in a different position; i

Figure'16 is a view of a switch illustrated in F igures 1 and 14 and showing the parts in a different position; and

modified form of a portion of the electro-. mechanical correcting mechanism.

--The master clock with which my resent invention hasbeenincorporated is il ustrated, described and claimed in my Patent N0. 1,492,318, but the construction and operationof this clock will be 'hereinbriefly described to permit a more ready understanding of the construction and operation of the combined mechanism.

J ournalgd in-the parallel plates 10 and 11 .of the clock frame are five parallel shafts 12, 13, 14, 15 and a composite shaft'S. These shafts are substantially as illustratedin my prior application; with the exception of shaft S'which is considerabl modified to'aid in the-accomplishment of present invention. The shaft 12 the minute hand shaft, which has ,rotatably mountedthereon at its outer end the usual hour hand sleeve 16. The usual reducing gear R operatively connects the inner end- .large gear 19 having a sleeve 20, a spring 21 being provided for forcing the gear 19 against the pinion 18 for frictional'engagement. This frictional engagement, is sufiicicntfor-driving the hands whileit permits the I nds to be moved manually in setting the clock without necessitating the rotation of the gear-.19 and the other gearing of the clock. Shaft 13 is'an intermediate or idler shaft and has fixed thereon a pinion 22' meshing with the gear 19 and a gear 23 which meshes with a pinion 24. The shaft 15 is an escapement shaft having at its rear or inner enda crank 25 the horizontal end portion 26 of whichcoop- T erates' with a. slotted plate 27 secured to the pendulum 28: Rotation of the shaft 15 causes the arm 26 to bear alternatelyon the Figure 17 IS a diagrammaticv view-10f. a

the objects of' the 100 asst answers com emons gear 30 on shaft 14, which is asecond idler.

T shaft and has rigidly mounted thereon a pinion 31 which meshes with a large gear 32011 shaft 5.

Referring particularly to Figure 6 it will be seen that the shaft S comprises. two co axial and relativelyrotatable portions, the rear portion 33 having a reduced forwardly extending axial portion or spindle 34 whichis received within a correspondingly shaped, axialrecess in shaft 35. l I he gear ,32 pre viously referred to is fixed on the forward end .ofthe main portion of the shaft 33 and has secured concentrically thereto an annular.

friction member 3630f angular crosssection, the inner margin of WhlCl'l has ltsrrearwardly directed face pressing against the outer-face of a disk 37 which is fixedon the inner-end of shaft 35. The degree of pres-I sure exerted by friction member 36 on the disk 37 may be varied by adjusting screws 38.

-The shaft 33 is the drive or power? shaft -of the clock and-the shaft is, the second hand supporting-"shaft; and these shafts are I normally 'operatively clutched together by the friction clutch just described, but when a tor us is exertedon the shaft 35 to cor--- rect tie position of the second hand the clutchwill slip, allowing the second hand I shaft to be rotated independentlyof the drive shaft so that such friction will not .interfere with the drijxin mechanism. 'As

the hour and minute him shafts are drivenby the pinion 24 which is fast on the shaft 35, and the pendulunfi's driven from the gear 32 which is fast Ollgfillitft 33, it is evident'that the driving means, including the time measuring means er pendulum, is only frictionally connected to the time indicating means including the three handsupporting shafts, and that "when power is applied to one of the shafts to correct. the positions'of the several hands the driving mechanism will be 'unalfected.

Shaft 33 is driven by means of a coiled spring a which has one end secured to the frame and its other endsecured to an S shaped m niature b rotatale y mounted on.

shaft 33, this armature having a pawl c which cooperates witlv a ratchet wheel (1 fixed on shaft 33. A rocker e, pivot-ally secured to the frame has arms ex ending laterally above and below the shaft 33 and lying in the path of a pin f secured to the armature b. As the spring unwinds armature 2') moves in a clockwise direction (Figure 3) until pin f strikes'the upper arm of the --rocker, which then flies upwardly to close switch \V, controlling the circuit through electro-magnet g. This magnet immediately acts to turn armature i; to a vertical position during which movement the pin f strikes the lower arm of the rocker which snaps downwardly and opens'switch \V. TlllS action,

insulating material of the shape clearly shown in Figure 12 is fixed onthe second hand shaft in front ofthe plate ligand this camfcloses the switch 'controllin the electrical circuits through the secondary clocks once each minute, so 'thatthe hands of such secondary clocks will be advanced at ,the'

minute intervals. The Jsecondary' clock switch comprises spring contact blades'43 and 44 which are insulated from each other and-from the frame, being secured a't-their lower'ends to an insulating block'45l The,

cam has a longitudinal radial face-and as a it rotates the ends of-contacts 43 and 44 pass overthe sharp edge of the cam once each minute andmove radially toward the shaft 35. The blades 43 and 44 are, however, of unequal length and blade 44, being the shorter of the two blades, will fall about v two secd'nds before the blade 43 thereby bringing the contact point 45 of blade 44 against contact point 46 of blade 43 and completing the circuit through the secondary clock system. 'As cam 42 continues its rotation, however, the blade 43 will move relatively to the blade 44 and will separate the two contacts 45 and 46 breaking the cir cu'it through the secondary clocks.

It will be apparent that if the angular position of the second hand shaft is changed that the angular position of the cam 42 will be simultaneously changed, .and the timing of the secondary clocks changed I exactly as the timing of the master clock.

The mechanism for correcting the position of the hands of the clock daily will now be described. It will be observed in this connection that the average masterclock will vary' only a few' seconds within 24 hours and I have therefore positioned the hand-correcting means to cooperate with the second hand of the clock in which position it will be effective to make corrections of errors as-large as' 20 or 25 seconds whether the clock be either fast or slow, but itwill be understood that. the correcting .or synchronizing mechanism maybe applied to an intermediate shaft .or to the minute shaft as desired for the correction of greater errors. Pivotally connected at 47 to a bracket 48 secured to the frame of the clock is a lever 49 extending transversely and parallel to the front plate 11, the free end of this lever being connected by means of a link 50 to the armature 51 of a solenoid elcctro-magnet 52 secured to the face plate 11;

I islever 49 lies directlybelow the pin 40 of t'e disk 39 and is provided with a'slot 53, the sides of which are arcs of circles described about the pivotal axis 47'and which is adapted to receive, when the lever 49 is moved upwardly, both the second shaft 35' and the pin 40. The upper end oi the slot- 53 is-o n for this purpose and the upper edge 0 the lever has two inclined'portions 54 adjacent the mouth of the slot for 'ding the pin 40 into the slot when the ever is raised. The'solenoid ,52 is connected in an second shaft 35, asthe pin will ride down" electrical circuit which includes a'hattery' 55 and a control switch (56 having a fixed contact 67 and a movable contact 68 which is resilient and normally tends to remain out of contact with the fixed contact 67. .VVhenever, however, thespring contact 68 has been moved to close the-switch the armaturetil will immediately more vertically upward thereby raising the-lever 49 and movingthe pin 40'to a position vertically above the the inclined edge or cam 54 and enter the slot This of course rotates the second hand "shait which will cause the hand 41 to assume its vertical or zero position,'which position it' should of course occup at 12 oclock noon-at which time switci is closed by mechanism now to be described.

It will be seen from Figures 4 and 14 that an insulating block 69 is secured to the re-,

silieut switch blade-68, this .block having a. raised portion at its upper end. A segment-al member 7 0 is pivotally supported adja- -ccnt the switch 66 and is provided with a pin 71, the path of rota-- laterally cxtendi'n tion of which about the pivotal axisof member 70 asses through the raised portion of insu ating'member 69. ,When the niemher-70 is rotated in a counterclockwise switch and, if it has been rotated through a sullicient angle, the spring will impart to it sullicient energy for this purpose but the strength of the spring 72 is such that the member 70 will not have sufiicientvenergyflto close the switch unless it has been rotated through a rather wide angle and then released. It will be seen that one edge of member 7 O, that is, the edge'opposite pin 71, is circular and is providedavith eleven teeth 73. These. teeth' cooperate with a dog 74 segment 70 is rotated through a sufiic'ienti pivoted to the frame of the machine and a.

BEST A JAlL -XBLE COPl indicated by the full and dotted line-pnsi tions in Figure 14. The lever 76 to which the pawl is pivoted, is pivoted at 78 to the armature 79 of a solenoid 80 secured to the frame'of the machine, and is provided at-its free end with a projection or boss 81 which extends'upwardly and lies in the vertical (plane of a roller 82 which is fastened to an extends laterally from the pendulum. \Vhen the pendulum is in its central position the roller 82 lies directly above the boss 81. 2

' Normally the lever 76 rests upon a bracket 83 secured to the frame' of the clock but when the solenoid 80 is energized, it will be raised, lifting pawl 7 5 and bringing the boss 81 into the ath of the swinging roller 82.-

In its raise osition spring 84 throws the upper end of .t 1e pawl into engagement with the uppermost tooth fot the eleven teeth 73 and, as lever 76 is rocked by the roller 82 of -the swinging pendulum once each sec-4 0nd, the pawl 75 will be effective in rotating the toothed. segment 70 one tooth per second. Thetdog '74 prevents return of memit will be obvious that in ten seconds the segmental member 70 will have been rotated through an-angle equal to the-angle subtended by ten consecutive teeth 73. Further rotation "of segment 70 is impossible .since there are-no more teeth for pawl'75 to en- 'gage. .If, after segment 70 has been rotated in this manner, dog 74 should be disengaged fromthe lowermost tooth 73 the segment will instantly rotate under the in fiuence of spring 72 and close the switch 66.

The spring is, however, of such acstrength, as previously pointed out, that the segment -will not have sufficient energy to close the nine of the ten teeth.

The means for opening switch.66 comprises a lever 85- pivoted to the frame of the clock and having at its free end an deenergized this spring will move the levern ward until the pin 87 engages an inclined e go 89 of segment 70. This edge 89 acts as'a cam and when it is struck by pin 87 the angle in nc e twise direction. to cause pin her 70 under. the influence of spring 72 and Y switch unless it has. been rotated at least' lilO S B r" r -I dlg ftVi-iiti i inz: COPE I -71 to disengage block 69 and to allow switch depending rod 107, the lowerendof which 66 to open. When pawl 75 is acting to rotate'se cut '70, however, the pin 87 is llgld clear of 70 by the action of the solenoid The electro-magnet 80 is connected in circuit with a battery 90 and a switch indicated generally at 91-. This-switch, which comprises two resilient-contact bladles 92,- 93, having suitable contact ints at their lower. ends is closed at approxunatel two minutes before the instant of noon eac day. When the switchis closed the pawl 75 will of course be raised and the rotation of segment 70 will be begun. Secured to switch blade 92 is an insulating block 94 having at its lower end a small raised portionpr bead 95 which lies in the'path of a pin 96 mounted on an arm 97 which is secured to .the hour sleeve so thatit describes twocomplete revolutions in .24 hourswip revent the switch 91 from being closed twice in a. 24 hour period, howeven means is provided for causing the pin 96 tonnes the projection 95 upon one rotation of. the arm 97. "This -.--1'neans comprises a plate 98 having a-circular opening 99 therein concentric with the axis of the hour sleeve and having also a a 100 at the top, the ends of which are'ra ia and-one of which is formed as a knife edge 101. Secured to the top of the plate 98 1s a U-shaped member 102 having depending legs extending downwardly on opposite sides of the plate and opposite the gap 100. The inner surfaces of these legs are rounded, as clearly shown in Figurest) and 10 and act as guides for the flexible circular extension 103 to arm 97. As this flexible extension 103 passes gap 100, as it does each 12 hours, it is guided -from one side of the plate 98 to the other by member 102. In Figure 10 it is shown passing from the front side of the plate to the rear side and in Figure 9 from the rear side to the front side. Only when the arm 103 is on the front side of. plate 98 can pin 96 engage the projection 95 as it passes block 94. This is clearly shown in Figure 8, and it will also be seen that pin 96 is extended through arm 97 and, when projection 103 is on the rear side of the plate, is in position to contact with, in its downward movement, an arin 104 which is rigid on an arbor 105 journaled in the plate. This arbor supports at its forward end a substantially triangular cam member 106 which bears against the flexible contact 93.

In order that the switch 91 be closed it IS necessary that cam 106 be set in the position shown in Figure 1 1 and that the pin 96 be .in engagement with projection 95. This dual control otthe switch is provided so that it may immediately be opened after the time correction has been made, and for this purpose arm 101 is provided with a lies in the path of the setting lever 49. As soon as the lever 49- is raised therefore, to

set the clock, it ogvens the switch 91" by raising arm 104'there y rotating cam106. Af-

ter arm 104 is raised in this manner it will arm .97 has 'a ain' moved it downwardly 12 hours later. lever 76 is lifted into operative position beremain in such position (Figure 7) until j t will be seen therefore that tween one and two minutes before the noon signal is expected and is dropped into inoperative position immediately of the clock, and that switch 91 will be closed only at noon, and not 12- hours later or at midnight.

ove described will of The mechanism a course effect the setting of the handsuapproximately at the noon hour, that is, wit

in a minute or two of noon and would not operate again until the following noon, but such setting would be entirely inaccurate after settingwithout the controlling devices therefor,

now to be described.

It will be observed that in Figure 14 the pawl 7 5 has a wedge shaped member 108 secured member not only comprises a cam, cooperating with the fixed stop 109 to throw the pawl 75 away from segment 70 as it'falls and also to throw dog 74 out of engagement with the segment, but also constitutes an armature for electro-magnet 110, which is secured to theframe of the clock adjacent thereto. This electro-magnet is in circuit with the battery 111 and the armature 112 of an electro-magnet 114. A spring 113 normally tends to close the circuit through magnet '110. Electro-magnet. 114 is however normally energized, and prevents the closing of this circuit except when deener-' gized. This electro-magnet 11 1 is in circuit with a battery 115 and a movable lever 116 which constitutes one member .of a relay adapted to act when energized by the faint impulses received from a wireless receiving apparatus, (not illustrated). This relay is fully described and claimed in my oopend- "ing application. Serial Number 455,261, filed March 24, briefly described.

The lever 116 is pivoted on a knife edge 117"and a spring 118 normally tends to rotate it about its pivotal axis so that itsopposite end will disengage the adjustable contact 119. An adjustable screw will disengage the adjustable contact 119. An adjustable screw 120 extends laterally from the I lever 116 at its quarter point and the'end of this screwabuts against a soft rubber sleeve 121 which covers the end of a second and parallel lever 122. The lever 122 has its opposite end pivotally mounted upon a knife edge 123 and a spring 124 tends to rotate this lever about its pivotal axis, maintaining thereto adjacent. its lower end.

1921, and-will herein be only 55' ceding the noon signal 'ten wireless signals 8E8? AVAiLABLE COPE it in contact with a'projection 125 on the vibratory diaphragnf 126 'offtlePhone-receiver 1'27, VVims 128 eorinect 1.27;

4' ing v apparatus .vyhieh may also he I: of well known tgpe ior instanee the .DeForst'rqj jof t lum f the clock'at second intemi '108 therefore 2. .mceivednwhichc which may he of-any-mfell known typesueh. as the Brandes' receiven, to-wireless receiv+ ceiving set; The 't"' '-thtongh' battery 115 and mag'netgllfis normall dosed 1m whendiaphragni'mfiiiis'caused' to due to the reception {of aigsignal". 1th

wireless reeeivmg' set; the even-I16 circuit; mgeee ine-is inmaiatei gi ep -gized and spring,1'13"aets e-circu at. be

i nw p i n l r dip for closin switch 1 6.6: .{Ifhatfis ja r -the switch 91- as-heen closed approximately; two minutes befor'ef noonia'nd .pawl '75 his been thrown into operative position .to

the magnet 110 will ajctjatseoond .to' prevent theoonipletion of the meee ssary' winding movement by the'pawhi sglong a;

'.the 29th second thepawl-will b'e iibljqad-K. -varice' the. segment 1 one 'tooth'. biit' tliis" ad-.f;

- with teeth-73L As the th through i.

. 30th second, since; ma

corrected. Movement the lever-49 emit-l the switch 91 to o' (Figure 16), nrmntme 86 is released and even 85 becomes operative to move segmentto open the switch 66 so .e

that the levef=49ngain may'inimediutely nergzedtheepavyl'm is of course thrown to nope'nitive positioning cam 108, as well as 3 1 m m n -pi es has again come inswitch 912' e 91:53 therefore a ieriod switch piihE-ZZ constitiite. rene spri or'; 1'n which energy. isfstored unt the proper instant. when'fiti'sgreleased to close e switch controlling'the hiznd'settin lever .4 In .Eig'ure 1'1 'is'illuetrated a modified form i mechanism forjbperntively-eonnecting the 1 52 of theiiendiiluni tontxtuting ther'no'vdo g fijso'that tlie moyement of segment .70

(me eewnwardly ta advance switch-blade 10 drogiso as'tohvoid im peding the progress e secondhand- \Vhenmagnet is dcnot' interfered-xvith The-action will notont'actwith the projection to close the inglconta'ct of the "switch controlliiig -this spring 12, byenergyimparted by the (hi-'- ci reuit and the flexible blade 153 constitutin}; the stationary contacti Normally the -contacts are'separated as show but when switch 91 is closed elehtfi magnet 1.54 is en.- .ergized and blade in weed-Se that it lies 1 the". impulses arefrecelved' .hj'flie inthe'pathibtpin 152, thus eausing a cona'pparatue, the pawl -75 cannotflaeoornplishf'tact once each second.' Ma'gnet 1511s ener- -thewinding-bnt when thesign'al's Lstop the -i' --gizcd therefo'r'at second intervals and acts pawl -7 5 will heleffeotive. For-instanee,=a.e

. to rock lever-155 at 'eah cnergization there- 'no signal' is received by" the wireless 'set fatll 'o'f, 'tb" advance the semnent 70. In some van'ce vvill belost .with'the arrival *offtheseconds are omitted fro;n the wireless .code' the minute but, u

the paizvlwill gain'five teeth at the'end'of fiy back to zero; position "but without. sufiicient force however to operate the .switeh 66.

diately raised am the hands of the clock ea. 11o 'vvill-again cases' this fo'mnof operatin mechanism will -he 'finefefned 'to the form-illustrated :in the 'otherfiirures of the drawings.

It-xvill be a art that the'e emnts and'component parts of (the invention may be differently arranged an limited therefore inits scope to the embodian the th. second, the me'nt disclosed, I pawl and dog -7 4 will agallnbe drawn out-bf Having 'thnsl described the invention what operative position and the segment 80 will I claim as new-and desiregto secure by Let- "ters Patent is:

Lil. clock includin' in combination, a drive shaft, a driven s aft, time indicating hand shafts moved by said driven shaft, means for driving eaid drive shaft, and vfriction meansconnectingsa id shafts -for I simultaneous rotation, Stl-ld'lilfi-RHS comprisiug two discs one-secured on each of said shafts, and a friction 'mexnber secured to one of said discs and' fric-tionally engaging thCOthOI.

2. A clo'ck including in. combination, n drive shafige. driven Sheft'coa'xial there parent to one skilled in the atlymodified. The invention is not directly connectin the drive shaft and sec- BEST AVAXLABLE com drive shaft, and friction meansconnecting said shafts for simultaneous rotation com-g prising two discs having contiguous faces and one being connected toeach of said' shafts, and a-=friction,=member secured to.

one of said discs and 'engaging. the other; 3. A clock including --in combination; a

drive shaft, means'gfo'; rotating'sllllait: s a our at uni-form s ed,' a' secpnd han and minute and shafts geared to said secondhand shaft, find -,5- friction device for.

' connecting said drive qshaftto said second hand shaft .whereby the hand shafts may be simultaneously. adjusted'r hti q to the drive shaft f u 4. A clock: including: estates, a. drive shaft, a clock train, handshafts con--v .nected-to.said train and adapted .be op erated' therby than" frictionfdevioi opera lively connecting saidgtrain'and powershaft whereby.- the train may be pendently ofth'e drive shaft.

5.---A clock includingimcombination, a 4 drive shaft, hour, minute and secondindicatin hand shafts,' and means connecting said hand shafts-to said drive shaft whereby the hand shafts may be operated,'--said means includin a single clutch 'through,

which motion of the shaft is transmitted to each ofjthe hand shafts and whereby the hand shafts may adjusted relatively to thedriveshaft.

6. ,A clock including in combinatiom-a drive shaft, a second hand shaft, hour and minute hand shafts, a; gear train 0 rative- 0nd hand shaft an also connecting the drive shaft to the hour and minute shafts through the gear train.

7. In the automatic correction of a cloclt' by recurrent electrical impulses separated by time intervals of different lengths through the medium of electrically actuated mechanism, the method of selecting an im-" ulsefollowing a relatively 'long interval etween impulses which comprises arranging said mechanism so as to tend to change its-condition durin the time that impulses are being received, ut to actually change to a radio receiver, an electro-magnetic de-.

4 rice actuated synchronously with current impulses delivered by said radio receiver, selecting-mechanism operated by said electro magnetic device and time controlled, in such manner that effective actuation therethe angular shaft comprising'incombination, a member .movable relatively to the shaft for rotating ad ustedL-indeof isbrought about only by a current impulse separated b an interval of predeter:

mined'minimum ength from the next preceding impulse, a control-switch closed by "said selecting mechanism -a second electronetic device and a clock 0' rated switchadiptedto cause the system to function only 'ma-lly transmitted 9. Mechanism periodically co'rre'ctin position- 'of. a rotatable cloc at times of day-when radio signals are nor-1 the same,- electromagneticmeans including a control switch for operating said member, 931 control i'switch at a predetermined instant the closure 'of said said meansjinclnding' a, second switch and a device for closing. said second switch once w in twenty four-hours.

10. Mechanism for. periodically correcting the. angular shaft comprising in combinatiom-a member movable relatively tosthe shaft for rotating the same, electromagnetic-means including a'control switchfor operating said member and a device forcifecting' the closure of said control switch ata predetermined instant said' device including a second switch andan element for closing said second switch, said '-element,being adapted to bemounted on the ho'u'rhaft of a'clock and rotatable therewith and having guiding i a ition of a rotatable clock means'to bringit into contact with said scc- 0nd switch '11. Mechanism for periodically correcting the angular position of a rotatable clock f shaft comprising 'in combination, a member movable relatively to the shaft for rotating the same, electromagnetic means including,

a control switch, for operating said member, means for efi'ecting the closure of said control switch at a predetermined instant, said means including a second switch having a device for closing said second switch and a device for opening said second switch immediately upon the movement of the first mentioned member.

-12. Mechanism for periodically correcting the angular position of a, rotatable clock shaft comprising-in combination, a member movable relatively to the shaft for rotating the same, electromagnetic means including a control switch, for operating said member, means for efiecting'the closure of said control switch at a predetermined instant, said means including a second switch having a device for closing said seconds\v1tcli-,.cam means for openingthe second switch immediately upon the movement of said first mentioned member.

iso

. element connectedto't'he, cam and lyingin 4. Mechanism for periodically v the angular position of a. rotatable clock- .ating. Suzi aestmanners-com movablerelatively to the shaft for rotating the same electromagnetic; means for 0 er-' memberghaving a; control switch,

and a device for closing the controlfiswitch whichlincludes a lever pivotally mounted on thearmature of a magnet one end of the lever adapted to be ven'ga ed b the pendulum,.' and the armature and ever ing moved into'pos'ition such that the lever is engaged by e means adapted tobe directly operated by 'magnefis energized.

said first mentioned member for opening the second-switch.

14. Mechanism for periodically'correcting the. angular "position of a rotatable clock" sft comprisin in oombina'tiom a' member movable relatively to tli shaft for. rotating the same, electromagnetic incensincluding a control switch, for operatiiigfsaid member, means, for effecting the closure of said con- .trol switch at a'predete'r "ned instant, said means including a second 5. and ademeans for opening 'said secondswitch.- ink mediately upon the movement iotsaid memberQ said second switch bav'mga cam, an

the path of movementof said member.

' 15. Mechanism for periodically correcting the angular position of'a rotatable shaft comprisingin' combinationa member m'ovahleirelatively.to'the shaft forlrotating the.

same electroma netic means for o ratin 3 l? C said member having a Control s\vitcli,-and

:1 device for closing the control switch which includes a member adapted to be operatedby a (lock pendulum.

. ihe same, electromagneticmeans for oper- :1n inoperative position, and-means for mov- 16; Mechanism for periodically correcting the angular position 'of a, rotatable ,cloek shaft comprising in combination, aancmber movable reiatii' elvl'o the shaft for rotating ating said member having a control siviteh, and a device for closingthec -control switch which includes a member-;:u]aptcd to be operated by a clock pendulum. but normally ing said member into position to beengaged by said pendulum, prior. to the operation of said control switch.

l'i. Mechanism for periodically correcting the angu ar p 'isition of a rotatable shaft; comprising in combination, a member movable relatively to the shaftfor rotating the same, leoirmnaguctic means for operating said member. having a control switch and a device for closing: the control switch which includes a 'nn-mbrr adapted to be operated by a clock pendulum, said member being provided -with electromagnetic means for moving the same into position to be engaged by the pendulum.

l8. Mechanism for periodically correcting the angular position of a rotatable clock shaft comprising in combinatior a member 19.,An'e1ectrica1 system for controlling apparatus in accordance with a code of electr'ic'al impulses, including in'combination, a

:movable member, clock controlled means operating only during .a fraction of the twenty-four hour period when the impulses pendulum, when said electro are being' translmitted and adapted during predetermined lintervalf between impulses te -move said member from an initial posi' tion to a". position, wherein-it is efiective to I control said apparatusand means 'for re-. vice for closing said second switch, "and;

turning .inember its initial position uponthe reception of each impulse, whereby the apparatus is cbntrolledbnly-uponfa ,prdetermined interval between" successive impulses;

20. A selective system responsive to a code of electrical impulses,".in'ciuding*in combination, a'rotatable member-b ased to giving an indication, and means responsive to the impulses for releasing said member and permitting it to return to initial posi .tion. upon the reception of each impulse,

whereby the indication is given only upon a. predeterminedinterval between successive impulses.

21. An electrical system for indicating time in accordance with a code of impulses including, combination, a movable member, means constantly tendingdur ng the time the"imp'ulses are being transmitted to move said'member from aninitial position to a position wherein 1%; is effective to con- .trol means for giving a time indication, and ,means responsive to the impulses for ret u rning said member to its initial position i'i'pon the rcccption'of each-impulse.

:22'. An electrical system for indicating time in accordance with a 'code of impu ses in clad g, in combination, clock controlled mechanism constantly operating only driring a fraction of the tnentv fourhour period when the impulses are "being transmitted and effective when'opemted a predetermined degree from an initial condition to control means for giving a time indication, and means for restoring said i 23, An electrical system time in'accordance with a code of electrical.

Ktrolling. said means, V

,ope'rating said impulse mechanism during" ception of each impulse.

for controllingv appara'tns. in accordance [with a code of elecntmoaej reception of; e ach impulse.

mechanism to its initial condition upon the";

for indicating impulses. including, in combination,- time 1nd1cat1ng meansflmpulse mechanism co nmeans constantly -'the time the electrical impulses are being transmitted, said impulse mechanism-being effective to control -sai d. ,time .indicating means only after it has beenoperatedfa predetermined degree from a certain condition, and means for restoring said impulse mechanism to saidv 'conditionupon the re- 24; A selective system trical impulses includingp'in combination;

for. operating said 7 impulse mechanism only during a fraction of the twenty four hour period when the electrical impulses are bemg transmitted, said impulse mechanism being efiective to control said apparatus only after it has been. moved 'predct'crmmed extent from its initial position, and means for returning said impulse mechanism. to' its initial position upon the reception or' each electrical impulse. p

25. A selective system -for-c0ntrol!ing apparatus in accordance with a code of elee-'- trical impulses. including, in combination, time indicating means COIDPIISIII" an electro magnet, a normally open switc hadapted to close the circuit of said electro magnet,

means for closing said switch includin step-by-step-mechanism biased to an mi tia position andjeifective to close the switch only after being operated a predeterminednumber of steps from its initial position,.'

and means responsive to'the electrical impulses for restoring said step-by-stepmechanisrn to its initial position upon the reception of each impulse. I I 26. An electrical system for indicating time in accordance with a code of electrical impulses including, in combination, a rotat-v able member biased to an initial position, clock controlled means constantly tending during the time the electrical impulsesware being transmitted to move said member from its, initial position to a position wherein it is effective when released to give a time' indication, and means responsive to the electrical impulses for releasing said member upon the reception of each impulse, whereby the time-indication is given only at the tel: mination of a predetermined hiatus in the .electrical impulses.

27. A selective system for controllinga ppnratus in accordance with a code of elec-- trical impulses, in combin ation, means including an electro-magnet for controlling the apparatus, impulse mechanism controlanism to initial sEsi" amnesia com .said' electro magnet, means controlled .by the clock for operating said im 11192:

mechanism during the time. electrica im' pulses are being transmitted, and means for restoring-said impulse mechanism. to its initial condition upon the reception of each.

electrical impulse, said im ulse mechanism being effective to control said electrc-magnet only after it has been operated .apredetermined degree from its initial condition.

28 A systemfor'setting' a clock. in.-response to a, code-of electrical impulses, in

' combinatiomimpulse mechanism controllin the setting of the clock, clock controlled means constantly operating; said im ulse twenty-four hour firiod when the electrical-impulses are ing transmitted, said impulsemechanismi efiective-to' set-the impulse'mechanism, clock controlled means clockonly-after it has beeni'operated a predetermined. degreejrom its initial position,- and'means forreturnin-gsaid impulsefmecliposition upon the reception ofeachimpulse. 9- j 29., A system for setting a clock in accordance-with a code ofelectrical impulses, in combination, timexeontrolled means 0 rmechanism only during. a fractiono the ating during the transmission of imp s, f

means for setting the clock uponthereceptlon of a slgnal impulse if, and only if,'sa1d' time controlled means has operated a predeterminedv extent from a certain condition, and means for preventing said time controlled 'means from attaining a saidprede- .termined' extent of operation so long as the signalimpulses are received at predetermined intervals apart. 7

30. A system for setting a clock in accordance with a code of-electrical impulses, 'm

combination, time controlled means automatically'sset in operation approximatel at the beg nning of the time signal impu ses, means for setting the clock upon the reception oia signal impulse if, and only if, said time controlled --mea nshas attained a prede- 'termined extent .of operation with respect to a certaincondition, means for-preventingcal impulses, including, in combination,- time controlled'means set. in o eration approxiof impulses and effective to control the. apparatus only after having been operated a 'niately at the beginning 0 "the transmission predetermined degree from its initial con dition, and means to restore said timecontrolled means to. its initial conditionv upon the reception of each'electrical impulse.

82. A system for setting a clock in accordance with a code of electrical impulses including. in combination, mechanism operated by the clock and constantly tending to move to a position wherein it is effective to set the clock, said mechanism being set in operation approximately at the beginning of the transmission of impulses, and means responsive tothe electrical impulses to restore said mechanism to its initial position upon. the reception of each impulse.

33. A. system for setting a clock in, ac.- cordance with a code of electrical impulses, including, in combination, mechanism adapted when uninterruptedly operated for a certain interval of time to attain a condition in which it is efi'ective to set the clock, means for setting said mechanism in operation approximately 'at the beginning of the time signal transmission and means for restoring said mechanism to its initial condition upon the reception of each signal impulse,

34. A selective system for controlling apparatus in accordance with a code of electrical impulses, including, in combination, mechanism adapted when uninterruptedly operated for a certain interval-of time to attain a condition in which it is efiective to control said apparatus, means for setting said mechanism in operation'approximately at the. beginning of the transmission of the electrical impulses, and means for restoring said mechanism to its initial conditi'on upon the reception of each signal impulse.

35. A system for setting a clock in accordance with a code of electrical impulses, in-. cluding, in combination, mechanism adapted when uninterruptedly operated for a certain interval of time to attain a condition in which it is effective to set the clock, means for setting said mechanism in operation approximately at the beginning of the transmission of impulses, means for restoring said mechanism to its initial condition upon the reception of each, impulse, and means to discontinue the operation of said mechanism when the clock is set.

36. A system for setting a clock in accordance with a code of electrical impulses, including, in combination, time controlled means set in operation approximately at the beginning of the transmission of impulses, means for setting the clock only after said time controlled means has operated a predetermined degree from an initial condition and a signal impulse is received, means for restoring said time controlled means to initial condition upon the reception of each impulse, and means for discontinuing the operation of said time controlled means when the clock is set.

-37. A selective. system for controlling apparatus in response to a code of electrical impulses, including, in combination, means for controlling the apparatus, step-by-step she to the impulses for mechanism controlled by the clock adapted to render said means operative to control the apparatus on movement through a predetermined number of steps, and an electromagnet controlled by theelectrical impulses governing said mechanism and preventing effective movement thereof so long as the impnlscsare being received at predetermined intervals.

38. In a system for indicating time in accordance with a code of electrical impulses, time controlled means automatically set in operation near the beginning'of the transmission of impulses, means for giving a time indication 'upon' the reception of an impulse if, and only if, said time controlled means has operated a redetermined extent with respect toan initial condition, and means for preventing said time controlled means from attaining said' predetermined extent of .operation so long as the impulses are received at predetermined intervals apart.

39. In a system for settin a clock in accordance with a code of electrical impulses, in combination, normallyinoperative stepby-step mechanism adapted to be operated by the clock, means controlled by the clock for rendering said mechanism operative approximately at the beginning of the transmission of impulses, means for setting the clock upon the reception of a signal impulse if, and only if, said step-by-step mechanism.

has been operated through a predetermined number 0t steps fromits initial position, means for preventingsaidmeehanism from attaining said predetermined extent of operation so long as the signals are received at predetermined intervals apart, and auto-' matie-means for discontinuing the operation of said step-by-step mechanism when the clock is set.

40. A selective system for closing a switch in response to a code of electrical impulses including, in combination, normally inactive power operated means efi'ective when 0 er ated through a predeterminedphase to c ose the switch, means independent of the impulses for initiating the operation of said first mentioned means and means responsive to the impulses for controlling said first mentioned means.

41. A selective system responsive to a code of electrical impulses including, in combination, a changeable medium, means for causing said'medium to change during intervals between impulses, means controlled by said medium for giving an indication upon the reception of an impulse if, and only if, said medium has changed a predetermined degree from a certain condition, and means responpreventing said medium from attaining sai predetermined degree of change so long as the im ulses are received at predetermined interva s, whereby the indication is given only upon a pre- BEST AVAlLABLE COPa determined interval between successive imelectrommgnet cpntrolled. by the signals pulses. governing said mechanism so as to'prevent 10 42.111 21 system for setting a clock in reit from setting the switch so long as the sponse to a code of signals, means fer setting signals are being received at shorter in 5 the clock including an electro-magnet, a tervals.

control switch therefor, mechanism .for set- In testimony. whereof I hereunto afiix my ting the-switch after a predetermined intersignature.

al in a series of electrical impulses and an THADDEUS STEPHENS 

